1. Field of the Invention
The present invention concerns a plug connection for an ink supply.
2. Description of the Prior Art
As used herein, a plug connection means an ink connection holder for ink print heads or for special ink cartridges of an ink printing system that is suitable to establish a detachable connection between an ink print head or a special ink cartridge and a rapid action cartridge coupling and a fluid connection with a tube system. For example, such an ink connection holder serves as a cartridge connector and can be used in maximally loaded ink printing systems which, among other things, are used in franking machines and in mail processing apparatuses that print a very high number of mail pieces.
A device for ink supply of a print head is known from the European Patent EP 733 481 B1. An ink reservoir can be connected with the print head. This ink reservoir is equipped with a pressure regulation that prevents the negative pressure in the ink print head from varying.
Furthermore, ink printing systems are known that essentially consist of a special ink cartridge with an ink reservoir, with a connector to the ink supply and with an ink print head; a tube system with pressure regulation; and an ink tank, available from Hewlett Packard Development Co. Further details of the special printing system from HP can be learned at the Internet site http://www.hp.com/oeminkjet.
The connection between the special ink cartridge with the ink reservoir and with the ink print head (FIG. 1) and tube system is produced by a securing cap (FIG. 2) and a rapid action cartridge coupling (FIG. 3) such that initially the securing cap is placed on a connector of the ink cartridge for ink supply to the ink print head, and then the rapid action cartridge coupling is plugged into the securing cap. For the ink connection, a hollow needle is pushed into a septum, and finally the rapid action cartridge coupling is connected with the special ink cartridge or with the ink print head by being pushed further by means of a latching mechanism (snap-in) in the securing cap (FIG. 4).
A significant disadvantage of the aforementioned solution is that there is no detachment capability of the rapid action cartridge coupling from the connector of the special ink cartridge, or the ink print head, when the useful life of the ink print head is reached. If the special ink cartridge need not be exchanged, the securing cap must be destroyed since the cap is not placed on the connector of the special ink cartridge, or the ink print head in such a manner that it can be detached without destruction.